Microporous battery separators including polyolefin layer and non-woven layer with alkylbenzene sulfonic acid lithium salt surfactant, lithium batteries utilizing the same, and methods of manufacture of the same

• US 10,741,814 B2
• Filed: 05/05/2016
• Issued: 08/11/2020
• Est. Priority Date: 05/08/2015
• Status: Active Grant

• Current Assignee: Celgard LLC (Asahi Kasei Corporation)
• Original Assignee: Celgard LLC (Asahi Kasei Corporation)
• Inventors: Adams, Changqing Wang, Wensley, C. Glen, Reinartz, Stefan
• Primary Examiner(s): Cullen, Sean P
• Application Number:
  US15/146,936
• Publication Number:
  US 20160329541A1
• Time in Patent Office: 1,559 Days
• Field of Search: 429144, 429250, 429254
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 4/5825 Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
• CPC Class Codes: H01M 50/403 Manufacturing processes of separators, membranes or diaphragms
• CPC Class Codes: H01M 50/417 Polyolefins
• CPC Class Codes: H01M 50/44 Fibrous material
• CPC Class Codes: H01M 50/454 comprising a non-fibrous layer and a fibrous layer superimposed on one another
• CPC Class Codes: H01M 50/457 comprising three or more layers
• CPC Class Codes: H01M 50/489 Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties
• CPC Class Codes: H01M 50/494 Tensile strength
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

In accordance with at least certain embodiments, the present invention is directed to novel, improved, coated, or treated separator membranes, separators or membrane based separators for lithium batteries. The membranes or separators may include non-woven layers, improved surfactant treatments, or combinations thereof. The separators or membranes are useful for solvent electrolyte lithium batteries, especially rechargeable lithium ion batteries, and provide improved performance, wettability, cycling ability, and/or recharging efficiency.

Claims

1. A microporous battery separator for a lithium battery, comprising:

a) a polyolefin layer which comprises at least one membrane of polypropylene; and

b) at least one non-woven layer on each side of the polyolefin layer, wherein the non-woven layer comprises polypropylene, and wherein the separator has a surfactant coating thereon and wherein the surfactant coating consists essentially of a lithium salt of a linear or branched alkylbenzene sulfonic acid depicted in the following chemical structure;

2. The separator according to claim 1, wherein the surfactant is present in an amount from about 0.1 to about 10.0 wt %.

3. The microporous battery separator of claim 1, wherein n is >

8.

4. The microporous battery separator of claim 1, wherein n is 12.

5. The separator according to claim 1, wherein the non-woven layer comprises a non-woven layer having a melting point less than about 200°

C.

6. The separator according to claim 1, wherein the non-woven layer further comprises polyethylene, low density polyethylene, polycarbonate, polyethylene terephthalate, polybutylene terephthalate, polymethylpentene, polystyrene, polyamide, polyimide, nylon, or a combination, blend or mixture thereof.

7. The separator according to claim 1, wherein the polyolefin layer comprises at least one membrane of polypropylene.

8. The separator according to claim 1, wherein the polyolefin layer further comprises at least one membrane of polyethylene, polypropylene, or a combination, blend or mixture thereof.

9. The separator according to claim 1, wherein the polyolefin layer comprises multiple layers of polypropylene, or multiple layers of polyethylene and polypropylene.

10. The separator according to claim 9, wherein the polyolefin layer is selected from one of the following multilayer arrangements:

PP/PP, PE/PP, PP/PE/PP, PE/PP/PE, PP/PP/PP, PP/PP/PP/PP, PE/PP/PP/PE, PP/PE/PE/PP, PP/PP/PP/PP/PP, PP/PP/PE/PP/PP, PP/PE/PP/PE/PP, PE/PP/PE/PP/PE, PP/PP/PP/PP/PP/PP, PE/PE/PP/PP/PE/PE, PP/PP/PE/PE/PP/PP, PP/PE/PP/PP/PE/PP, PE/PP/PE/PE/PP/PE, PP/PE/PE/PE/PE/PP, and PE/PP/PP/PP/PP/PE.

11. In a lithium battery, the improvement comprising the separator of claim 1.

12. An energy storage system comprising one or more LiFePO₄ batteries comprising a separator according to claim 1.